DESCRIPTION OF SPECIES— GEAMINE^. 89 



articulations flexuoiis branches nearly at right angle, two to three millimeters 

 thick, linear, with two or three rows of radicles, more or less regularly placed, 

 sometimes in lines, sometimes distributed without order, filiform ; the stems 

 articulated also, bearing scars of branches at the articulations, and striate in 

 the lengtli, like the leaves, with primary veins distinct, about two millimeters 

 distant, and three to six thin veinlets between. As the plants of this kind 

 were very large, easily crushed on account of their hollow stem, they are 

 merely found in fragments ; at least, we have never seen, in our Lignitic 

 formations, large specimens of them; and these fragments, though referable 

 to the typical forms, present a great diversity of shape. It is, therefore, 

 probable that some of the references are uncertain, and that, when the species 

 is known by better specimens and more distinct characters, some of the 

 vegetable organs considered as pertaining to this species will have to be 

 distributed with other kinds of vegetables. Thus the roots and rootlets first 

 mentioned in Annual Report, 1870, p. 384, as rather comparable to those 

 of Phragmites CEningensis, have been recognized and described (pi. vi, 

 fig. 1) as those of a Fern, Lygodium neuropteroides. It must be remarked, 

 however, that when these specimens were examined, they were the first ones 

 seen from the Western Tertiary Measures, when we had no point of com- 

 parison whatever. This deficiency was already supplied, in a certain degree 

 at least, for the Report of 1871, and here we have (p. 286) the species 

 mentioned in numerous fragments of leaves, stems, and rhizomas from Elko 

 Station. Then (p. 289) a fine stem, with articulations, scars, and branches, 

 is identified with this species, from Medicine Bow's coal beds, whose station 

 is referable to the Washakie group. In the supplement (Report, 1871, p. 10), 

 a stem from Evanston is described, about half an inch broad, with primary 

 veins deeply marked, strong, separated by thin intermediate veinlets, articu- 

 late, bearing at the articulation the round scar of a branch. It is more 

 deeply striated than in most of the specimens figured of this species, agree- 

 ing, however, with a branch described by Sismondi (Pal^ont. du Pidmont, 

 p. 410, pi. vi, figs. 3-5). A stem of the same kind, and with the same char- 

 acter of nervation, is also mentioned in the same supplement (p. 13) as found 

 with fragments of Abietites dubius at the Raton Mountains. In Report, 1872, 

 p. 376, a fine specimen, with an articulation and scar, is described from the 

 white sandstone under the Lignite beds of Golden. It is the specimen of our 

 pi. viii, fig. 1. At the same locality, Prof B. F. Meek di.scovered a number 



